diff --git a/http/handler.go b/http/handler.go
index 787cf3b9c..0ca637871 100644
--- a/http/handler.go
+++ b/http/handler.go
@@ -258,24 +258,24 @@ func (h *Handler) handleHome(w http.ResponseWriter, r *http.Request) {
 	http.Error(w, "Welcome. Pilosa is running. Visit https://www.pilosa.com/docs/ for more information.", http.StatusNotFound)
 }
 
-// checkHeaderAcceptJSON returns true if one or more Accept
+// validHeaderAcceptJSON returns false if one or more Accept
 // headers are present, but none of them are "application/json"
-// (or any matching wildcard). Otherwise returns false.
-func checkHeaderAcceptJSON(header http.Header) bool {
+// (or any matching wildcard). Otherwise returns true.
+func validHeaderAcceptJSON(header http.Header) bool {
 	if v, found := header["Accept"]; found {
 		for _, v := range v {
 			if v == "application/json" || v == "*/*" || v == "*/json" || v == "application/*" {
-				return false
+				return true
 			}
 		}
-		return true
+		return false
 	}
-	return false
+	return true
 }
 
 // handleGetSchema handles GET /schema requests.
 func (h *Handler) handleGetSchema(w http.ResponseWriter, r *http.Request) {
-	if checkHeaderAcceptJSON(r.Header) {
+	if !validHeaderAcceptJSON(r.Header) {
 		http.Error(w, "JSON only acceptable response", http.StatusNotAcceptable)
 		return
 	}
@@ -290,7 +290,7 @@ func (h *Handler) handleGetSchema(w http.ResponseWriter, r *http.Request) {
 
 // handleGetStatus handles GET /status requests.
 func (h *Handler) handleGetStatus(w http.ResponseWriter, r *http.Request) {
-	if checkHeaderAcceptJSON(r.Header) {
+	if !validHeaderAcceptJSON(r.Header) {
 		http.Error(w, "JSON only acceptable response", http.StatusNotAcceptable)
 		return
 	}
@@ -305,7 +305,7 @@ func (h *Handler) handleGetStatus(w http.ResponseWriter, r *http.Request) {
 }
 
 func (h *Handler) handleGetInfo(w http.ResponseWriter, r *http.Request) {
-	if checkHeaderAcceptJSON(r.Header) {
+	if !validHeaderAcceptJSON(r.Header) {
 		http.Error(w, "JSON only acceptable response", http.StatusNotAcceptable)
 		return
 	}
@@ -362,7 +362,7 @@ func (h *Handler) handlePostQuery(w http.ResponseWriter, r *http.Request) {
 
 // handleGetSlicesMax handles GET /schema requests.
 func (h *Handler) handleGetSlicesMax(w http.ResponseWriter, r *http.Request) {
-	if checkHeaderAcceptJSON(r.Header) {
+	if !validHeaderAcceptJSON(r.Header) {
 		http.Error(w, "JSON only acceptable response", http.StatusNotAcceptable)
 		return
 	}
@@ -384,7 +384,7 @@ func (h *Handler) handleGetIndexes(w http.ResponseWriter, r *http.Request) {
 
 // handleGetIndex handles GET /index/<indexname> requests.
 func (h *Handler) handleGetIndex(w http.ResponseWriter, r *http.Request) {
-	if checkHeaderAcceptJSON(r.Header) {
+	if !validHeaderAcceptJSON(r.Header) {
 		http.Error(w, "JSON only acceptable response", http.StatusNotAcceptable)
 		return
 	}
@@ -466,7 +466,7 @@ type postIndexResponse struct{}
 
 // handleDeleteIndex handles DELETE /index request.
 func (h *Handler) handleDeleteIndex(w http.ResponseWriter, r *http.Request) {
-	if checkHeaderAcceptJSON(r.Header) {
+	if !validHeaderAcceptJSON(r.Header) {
 		http.Error(w, "JSON only acceptable response", http.StatusNotAcceptable)
 		return
 	}
@@ -488,7 +488,7 @@ type deleteIndexResponse struct{}
 
 // handlePostIndex handles POST /index request.
 func (h *Handler) handlePostIndex(w http.ResponseWriter, r *http.Request) {
-	if checkHeaderAcceptJSON(r.Header) {
+	if !validHeaderAcceptJSON(r.Header) {
 		http.Error(w, "JSON only acceptable response", http.StatusNotAcceptable)
 		return
 	}
@@ -522,7 +522,7 @@ func (h *Handler) handlePostIndex(w http.ResponseWriter, r *http.Request) {
 
 // handlePostIndexAttrDiff handles POST /index/attr/diff requests.
 func (h *Handler) handlePostIndexAttrDiff(w http.ResponseWriter, r *http.Request) {
-	if checkHeaderAcceptJSON(r.Header) {
+	if !validHeaderAcceptJSON(r.Header) {
 		http.Error(w, "JSON only acceptable response", http.StatusNotAcceptable)
 		return
 	}
@@ -563,7 +563,7 @@ type postIndexAttrDiffResponse struct {
 
 // handlePostField handles POST /field request.
 func (h *Handler) handlePostField(w http.ResponseWriter, r *http.Request) {
-	if checkHeaderAcceptJSON(r.Header) {
+	if !validHeaderAcceptJSON(r.Header) {
 		http.Error(w, "JSON only acceptable response", http.StatusNotAcceptable)
 		return
 	}
@@ -645,7 +645,7 @@ type postFieldResponse struct{}
 
 // handleDeleteField handles DELETE /field request.
 func (h *Handler) handleDeleteField(w http.ResponseWriter, r *http.Request) {
-	if checkHeaderAcceptJSON(r.Header) {
+	if !validHeaderAcceptJSON(r.Header) {
 		http.Error(w, "JSON only acceptable response", http.StatusNotAcceptable)
 		return
 	}
@@ -675,7 +675,7 @@ type deleteFieldResponse struct{}
 
 // handlePostFieldAttrDiff handles POST /field/attr/diff requests.
 func (h *Handler) handlePostFieldAttrDiff(w http.ResponseWriter, r *http.Request) {
-	if checkHeaderAcceptJSON(r.Header) {
+	if !validHeaderAcceptJSON(r.Header) {
 		http.Error(w, "JSON only acceptable response", http.StatusNotAcceptable)
 		return
 	}
@@ -771,7 +771,7 @@ func (h *Handler) readURLQueryRequest(r *http.Request) (*pilosa.QueryRequest, er
 
 // writeQueryResponse writes the response from the executor to w.
 func (h *Handler) writeQueryResponse(w http.ResponseWriter, r *http.Request, resp *pilosa.QueryResponse) error {
-	if checkHeaderAcceptJSON(r.Header) {
+	if !validHeaderAcceptJSON(r.Header) {
 		return h.writeProtobufQueryResponse(w, resp)
 	}
 	return h.writeJSONQueryResponse(w, resp)
@@ -934,7 +934,7 @@ func (h *Handler) handleGetExportCSV(w http.ResponseWriter, r *http.Request) {
 
 // handleGetFragmentNodes handles /fragment/nodes requests.
 func (h *Handler) handleGetFragmentNodes(w http.ResponseWriter, r *http.Request) {
-	if checkHeaderAcceptJSON(r.Header) {
+	if !validHeaderAcceptJSON(r.Header) {
 		http.Error(w, "JSON only acceptable response", http.StatusNotAcceptable)
 		return
 	}
@@ -983,7 +983,7 @@ func (h *Handler) handleGetFragmentBlockData(w http.ResponseWriter, r *http.Requ
 
 // handleGetFragmentBlocks handles GET /fragment/blocks requests.
 func (h *Handler) handleGetFragmentBlocks(w http.ResponseWriter, r *http.Request) {
-	if checkHeaderAcceptJSON(r.Header) {
+	if !validHeaderAcceptJSON(r.Header) {
 		http.Error(w, "JSON only acceptable response", http.StatusNotAcceptable)
 		return
 	}
@@ -1019,7 +1019,7 @@ type getFragmentBlocksResponse struct {
 
 // handleGetVersion handles /version requests.
 func (h *Handler) handleGetVersion(w http.ResponseWriter, r *http.Request) {
-	if checkHeaderAcceptJSON(r.Header) {
+	if !validHeaderAcceptJSON(r.Header) {
 		http.Error(w, "JSON only acceptable response", http.StatusNotAcceptable)
 		return
 	}
@@ -1121,7 +1121,7 @@ func errorString(err error) string {
 }
 
 func (h *Handler) handlePostClusterResizeSetCoordinator(w http.ResponseWriter, r *http.Request) {
-	if checkHeaderAcceptJSON(r.Header) {
+	if !validHeaderAcceptJSON(r.Header) {
 		http.Error(w, "JSON only acceptable response", http.StatusNotAcceptable)
 		return
 	}
@@ -1162,7 +1162,7 @@ type setCoordinatorResponse struct {
 
 // handlePostClusterResizeRemoveNode handles POST /cluster/resize/remove-node request.
 func (h *Handler) handlePostClusterResizeRemoveNode(w http.ResponseWriter, r *http.Request) {
-	if checkHeaderAcceptJSON(r.Header) {
+	if !validHeaderAcceptJSON(r.Header) {
 		http.Error(w, "JSON only acceptable response", http.StatusNotAcceptable)
 		return
 	}
@@ -1202,7 +1202,7 @@ type removeNodeResponse struct {
 
 // handlePostClusterResizeAbort handles POST /cluster/resize/abort request.
 func (h *Handler) handlePostClusterResizeAbort(w http.ResponseWriter, r *http.Request) {
-	if checkHeaderAcceptJSON(r.Header) {
+	if !validHeaderAcceptJSON(r.Header) {
 		http.Error(w, "JSON only acceptable response", http.StatusNotAcceptable)
 		return
 	}
@@ -1243,7 +1243,7 @@ func (h *Handler) handleRecalculateCaches(w http.ResponseWriter, r *http.Request
 }
 
 func (h *Handler) handlePostClusterMessage(w http.ResponseWriter, r *http.Request) {
-	if checkHeaderAcceptJSON(r.Header) {
+	if !validHeaderAcceptJSON(r.Header) {
 		http.Error(w, "JSON only acceptable response", http.StatusNotAcceptable)
 		return
 	}