diff --git a/include/mapnik/metawriter_json.hpp b/include/mapnik/metawriter_json.hpp
index 5f250e3ee..35b879bd3 100644
--- a/include/mapnik/metawriter_json.hpp
+++ b/include/mapnik/metawriter_json.hpp
@@ -39,6 +39,7 @@ class metawriter_json_stream : public metawriter, private boost::noncopyable
 {
 public:
     metawriter_json_stream(metawriter_properties dflt_properties);
+    ~metawriter_json_stream();
     virtual void add_box(box2d<double> box, Feature const &feature,
                          proj_transform const& prj_trans,
                          CoordTransform const& t,
@@ -48,9 +49,10 @@ public:
     virtual void stop();
     void set_stream(std::ostream *f) { f_ = f; }
 
+protected:
+    int count;
 private:
     std::ostream *f_;
-    int count;
 };
 
 /** JSON writer. */
@@ -58,7 +60,6 @@ class metawriter_json : public metawriter_json_stream
 {
 public:
     metawriter_json(metawriter_properties dflt_properties, path_expression_ptr fn);
-    ~metawriter_json();
 
     virtual void start(metawriter_property_map const& properties);
     virtual void stop();
diff --git a/src/metawriter.cpp b/src/metawriter.cpp
index 40cf3aae3..8aad370ca 100644
--- a/src/metawriter.cpp
+++ b/src/metawriter.cpp
@@ -20,7 +20,6 @@
  *
  *****************************************************************************/
  
-
 // Mapnik
 #include <mapnik/metawriter.hpp>
 #include <mapnik/metawriter_json.hpp>
@@ -39,25 +38,46 @@ UnicodeString const& metawriter_property_map::operator[](std::string const& key)
 {
     std::map<std::string, UnicodeString>::const_iterator it;
     it = m_.find(key);
-    if (it != m_.end()) return not_found_;
+    if (it == m_.end()) return not_found_;
     return (*it).second;
 }
 
+metawriter_properties::metawriter_properties(boost::optional<std::string> str)
+{
+    if (str) {
+        boost::split(*this, *str, boost::is_any_of(", "), boost::token_compress_on);
+    }
+}
+
+/********************************************************************************************/
+
 void metawriter_json_stream::start(metawriter_property_map const& properties)
 {
     assert(f_);
     *f_ << "{ \"type\": \"FeatureCollection\", \"features\": [\n";
+    count = 0;
 }
 
 void metawriter_json_stream::stop()
 {
-    if (f_) {
+    if (count >= 0 && f_) {
         *f_ << " ] }\n";
     }
+    count = -1;
+}
+
+metawriter_json_stream::~metawriter_json_stream()
+{
+    if (count >= 0) {
+#ifdef MAPNIK_DEBUG
+        std::cerr << "WARNING: GeoJSON metawriter not stopped before destroying it.";
+#endif
+        stop();
+    }
 }
 
 metawriter_json_stream::metawriter_json_stream(metawriter_properties dflt_properties)
-    : metawriter(dflt_properties), count(0) {}
+    : metawriter(dflt_properties), count(-1), f_(0) {}
 
 void metawriter_json_stream::add_box(box2d<double> box, Feature const &feature,
                               proj_transform const& prj_trans, CoordTransform const &t,
@@ -69,11 +89,18 @@ void metawriter_json_stream::add_box(box2d<double> box, Feature const &feature,
         props = dflt_properties_;
     }
 
+#ifdef MAPNIK_DEBUG
     if (props.empty())
     {
         std::cerr << "WARNING: No properties available for GeoJSON metawriter.\n";
     }
 
+    if (count < 0)
+    {
+        std::cerr << "WARNING: Metawriter not started before using it.\n";
+    }
+#endif
+
     /* Coordinate transform in renderer:
        input: layer srs
        prj_trans.backwards()   [prj_trans: map -> layer]
@@ -130,11 +157,6 @@ metawriter_json::metawriter_json(metawriter_properties dflt_properties, path_exp
     : metawriter_json_stream(dflt_properties), fn_(fn) {}
 
 
-metawriter_json::~metawriter_json()
-{
-    stop();
-}
-
 void metawriter_json::start(metawriter_property_map const& properties)
 {
     std::string filename =
@@ -152,14 +174,14 @@ void metawriter_json::start(metawriter_property_map const& properties)
 void metawriter_json::stop()
 {
     metawriter_json_stream::stop();
-    if (f_.is_open()) f_.close();
-}
-
-
-metawriter_properties::metawriter_properties(boost::optional<std::string> str)
-{
-    if (str) {
-        boost::split(*this, *str, boost::is_any_of(", "), boost::token_compress_on);
+    if (f_.is_open()) {
+        f_.close();
     }
+#ifdef MAPNIK_DEBUG
+    else {
+        std::clog << "WARNING: File not open in metawriter_json::stop()!\n";
+    }
+#endif
 }
+
 };