diff --git a/doc/fixes3-7-0.txt b/doc/fixes3-7-0.txt
index fc8ce49e3..fc66d4e59 100644
--- a/doc/fixes3-7-0.txt
+++ b/doc/fixes3-7-0.txt
@@ -1414,6 +1414,7 @@ shopkeepers magnified the cost of shop items used up as a group; normally
 the tile for Ixoth (knight's quest nemesis) depicted a demon rather than a
 	dragon; change it to be a red dragon
 untrapping containers or doors gives some experience
+only honor DEBUGFILES (for activating debugpline() calls) when in wizard mode
 
 
 Fixes to 3.7.0-x General Problems Exposed Via git Repository
diff --git a/src/files.c b/src/files.c
index 8c69e9399..5a39296cd 100644
--- a/src/files.c
+++ b/src/files.c
@@ -4519,6 +4519,11 @@ debugcore(const char *filename, boolean wildcards)
 {
     const char *debugfiles, *p;
 
+    /* debugpline() messages might disclose information that the player
+       doesn't normally get to see, so only display them in wizard mode */
+    if (!wizard)
+        return FALSE;
+
     if (!filename || !*filename)
         return FALSE; /* sanity precaution */