diff --git a/bob/measure/script/commands.py b/bob/measure/script/commands.py
index 9c8ba0558111aa04dd13c7b626858f9767a8d58f..61d650a8a325a6b4d2e96aca213cc6f5b2d25fbb 100644
--- a/bob/measure/script/commands.py
+++ b/bob/measure/script/commands.py
@@ -118,7 +118,7 @@ def det(ctx, scores, evaluation, **kwargs):
     process.run()
 
 @click.command()
-@common_options.scores_argument(min_arg=2, nargs=-1)
+@common_options.scores_argument(min_arg=1, force_eval=True, nargs=-1)
 @common_options.output_plot_file_option(default_out='epc.pdf')
 @common_options.title_option()
 @common_options.titles_option()
diff --git a/bob/measure/script/common_options.py b/bob/measure/script/common_options.py
index 94bbed8ca475a12347fe3a09271a484a37dd453b..19331f86fc819ce60ce7275d7db2ba2459869d9c 100644
--- a/bob/measure/script/common_options.py
+++ b/bob/measure/script/common_options.py
@@ -9,7 +9,7 @@ from bob.extension.scripts.click_helper import (bool_option, list_float_option)
 
 LOGGER = logging.getLogger(__name__)
 
-def scores_argument(min_arg=1, **kwargs):
+def scores_argument(min_arg=1, force_eval=False, **kwargs):
     """Get the argument for scores, and add `dev-scores` and `eval-scores` in
     the context when `--evaluation` flag is on (default)
 
@@ -29,7 +29,7 @@ def scores_argument(min_arg=1, **kwargs):
             min_a = min_arg or 1
             mutli = 1
             error = ''
-            if 'evaluation' in ctx.meta and ctx.meta['evaluation']:
+            if ('evaluation' in ctx.meta and ctx.meta['evaluation']) or force_eval:
                 mutli += 1
                 error += '- %d evaluation file(s) \n' % min_a
             if 'train' in ctx.meta and ctx.meta['train']: